package com.lxx.bigevent.interceptors;

import com.lxx.bigevent.utils.JwtUtil;
import com.lxx.bigevent.utils.ThreadLocalUtil;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import java.util.Map;

@Component
public class LoginInterceptor implements HandlerInterceptor {
    @Autowired
    private StringRedisTemplate redisTemplate;

    /**
     * 这个方法是在访问接口之前执行的，
     * 我们只需要在这里写验证登录状态的业务逻辑，就可以在用户调用指定接口之前验证登录状态了
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        // 从请求头中获取token
        String token = request.getHeader("Authorization");
        // 验证token
        try {
            // 从redis中获取相同的token
            String redisToken = redisTemplate.opsForValue().get(token);
            if(redisToken == null) {
                // token已经失效
                throw new RuntimeException();
            }
            Map<String, Object> claims = JwtUtil.parseToken(token);
            // 把业务数据存储到ThreadLocal
            ThreadLocalUtil.set(claims);
            //放行
            return true;
        } catch (Exception e) {
            // http响应状态码为401
            response.setStatus(401);
            //不放行
            return false;
        }
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        // 清空ThreadLocal中的数据
        ThreadLocalUtil.remove();
    }
}
